<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <!-- 引入样式 -->
        <link rel="stylesheet" href="https://unpkg.com/element-ui/lib/theme-chalk/index.css">
    </head>
    <body>
        <div id="app">
            <el-container>
                <el-header>Header</el-header>
                <el-main>Main</el-main>
                <el-footer>Footer</el-footer>
            </el-container>
        </div>
    </body>
    <!-- import Vue before Element -->
    <script src="https://unpkg.com/vue@2/dist/vue.js"></script>
    <!-- import JavaScript -->
    <script src="https://unpkg.com/element-ui/lib/index.js"></script>
    <script>
        new Vue({
          el: '#app',
          data: function() {
            return { visible: false }
          }
        })
  </script>
</html>